Circuit interrupter



Oct. 26, 1954 c. scHlNnLER 2,692,925

'CIRCUIT-INTBRRUPTER Filed Aug. 28, 1951 4 Sheets-Sheet l Oct. 26, 1954 c. scHlNDLER CIRCUIT INTERRUPTER 4 sheets-sheet :s

Filed Aug. 28, 1951 "InIl IN VEN TOR fv/ l Qi/afer cp/way Oct. 26, 1954 C, 5CH|NDLER 2,692,925

CIRCUIT 'INTERRUPTER 4 Sheets-Sheet 4 Filed Aug. 28, 1.951

Y Z 7 4/7 j# p ce; ,I r *4 Mm Patented ct. 26, 1954 CIRCUIT INTERRUPTER Carl Schindler, Wauwatosa, Wis., assignor to McGraw Electric Company, Milwaukee, Wis., a, corporation of Delaware Application August 28, 1951, Serial No. 243,953

Claims.

This invention relates to circuit interrupters and is an improvement over the circuit inter'- rupters shown in the following patents which are assigned to the same assignee as the present application, viz. the patent to Van Ryan and Schindler, 2,560,529, of July l0, 1951, for Automatic Reclosing Circuitl Breaker, and the patent to Van Ryan and Schindler, 2,560,831, of July 17, 1951, for Circuit Interrupter.

In circuit interrupters as shown by the above noted patents and others of this general type, it is difcult to secure a very long path in the event an arc should strike from the contacts to metal parts of the body portion. If the distance from the lower end of the body portion 'to the contacts is increased, the total height of the circuit interrupter will become inordinately great and a longer enclosing tank as well as a considerable increase in the cost of manufacture will result. Further than this, it has been found diiiicult to detach the contacts and operating mechanism from the body portion without disturbing parts of the body portion such as the electromagnetic motor means.

This invention is designed to overcome the above noted defects, and objects of this invention are to provide a circuit interrupter which can safely interrupt circuits of higher voltages thus providing a circuit interrupter of a higher rating without unduly increasing` the sizes, particularly the length of the circuit breaker while at the same time providing greater insulating values by increasing the length of the arc path to metal parts of the body portion.

Further objects are to provide a circuit interrupter in which the contacts and operating mechanism therefore constitute a unitary operating mechanism and switch assembly, in which a pair or" insulating walls act not only as insulating barriers but also act as structural members, and in which the unitary operating mechanism and switch assembly can be removed or replaced as a unit without disturbing any portion of the body part of the circuit interrupter, particularly without disturbing the electromagnetic motor means.

An embodiment of the invention is shown in the accompanying drawings, in which:

Figure l is a side view of a circuit interrupter with parts broken away and parts in section.

Figure 2 is a detail fragmentary view partly in section showing the contacts and the operating mechanism in circuit closed position.

Figure 3 is a side elevation partly in section of the lower portion of the structure shown in Figure l with the parts in circuit closed position.

Figure 4 is a sectional View on the line 4 4 of Figure 3.

Figure 5 is a view corresponding to the lower part of Figure 3, showing the parts in circuit open position.

Referring to the drawings, it will be seen that the device comprises a body portion indicated generally by the reference character l, and an operating mechanism and switch assembly indicated generally by the reference character 2, and supported from the body portion in a manner hereinafter described.

The circuit nterrupter is housed within a tank 3 which is preferably lled with oil as disclosed in the prior patents hereinabove referred to.

The body portion may comprise a structure substantially similar to that shown in either of the above two patents and includes an electromagnetic motor means indicated generally by the reference character 4 which includes a plunger 5 operated by the electromagnetic motor means. This structure is more fully set forth in the above noted prior patents.

The operating mechanism and switch assembly indicated generally by the reference character 2 is a unitary structure and comprises a head portion 5 removably bolted or otherwise secured as indicated at 6 to the lower portion 'I of the electromagnetic motor means 4, see Figure 1. It is to be noted from reference to Figure l, that the securing means 6 may consist of bolts or screws which pass through the head 5 of the operating mechanism and switch assembly and are screwed into the lower head "l of the electromagnetic motor means 4.

This enables the repairman or inspector to remove the unitary structure consisting of the operating mechanism and switch assembly without disturbing any portion of the electromagnetic motor means d or any other part of the body p0rtion l.

The head 5 of the operating mechanism and switch assembly has side flanges 8 to which insulating side walls 9 are attached. These side walls 9 are relatively heavy insulating members and serve not only as insulating bailles but also as structural members and support the switch mechanism, indicated generally by the reference character ID as will be described hereinafter.

The switch mechanism comprises a pair of insulating tubular members H which carry terminals I2. The terminals support stationary contact members consisting of a pair of inwardly pressed spring fingers I3 as shown in Figure 2. The movable contacts are indicated at l4-I4 and consist of metal rods which are removably attached to a metallic crosshead I5. Preferably the lower portion of the tubular insulating members II are provided with inwardly projecting annular baffles I6 through which the rods Ill- I4 freely pass. The members il are connected and supported by a transverse tubular member I'I of insulating material.

One ofjthe. membersli has a relatively large opening I8 communicating with the interior of the tube II and the other member II has a relatively smaller opening IS communicating with the other end of the tube Il. The last mentionedgenerated-within the left hand tubular member II, see Figure 2, ,and oil is projected'violently across the arc formed in the other tubular member I I located on theright hand side of Figure 2 and -passes outwardly through the discharge openings 20. The switch mechanism. is connected -in series with the energizing coil of the electromagnetic motor means.

It is to be -noted that the insulating tubular members II extend through a top plate 2l of insulating material. Thistop plate is interlocked with the insulating supporting side plates 9 heretofore described. Preferably the members II are providedy with shouldered portions 22, see Figure 2,. which rest on the top plate 2l and split washers 23 engage grooves formed vin the lower portion of the members II and bear against the under side of thetubes I1 as shown in Figure .2, thus locking the members II in'place.y In order toV prevent relative rotation of the members II with respect to the tubes Il, each of the members vis provided Lwith a keypin 24. These key pins fit within corresponding. slots 25;A formed in the heavy insulating plate 2l, see Figure 2,1andfthus prevent rotation. of the-members II.

The crosshead I is provided with an elongated integral sleeve 26 which is slidably guided by a Vertical insulating guide rod 2T. The guide rod.'

is anchored at its lower end by a metallicsupporting member 28" and at-its upper end by a hole 29 formed inthe under side of the tube-I1;

as shown in Figure 2.

The operating mechanismf for moving theL bers 32 and A33,and\ consequently operate as a' single member having two arms. The lever 3|! therefore, will be hereinafter referred to merely'V as a single llever having two arms. The arms of the lever 3B are connected to the'crosshead by means of Va pair'of links'34 and 35i The inner links 35 'are formed integrally and are joined by means of a U shaped member 36.

It will be notedv from the construction described. hereinabove that the` crosshead I5 is prevented from turning or rocking on the vertical supporting rod 2l since the links 35 will prevent such motion as they are attached both to the arm of the lever 30 and to the crosshead I5 as shown in Figure 2, and are integrally joined together.

The operating mechanism includes all of the structure which -is interposed between the plunger 5'f'of the electromagnetic motor means 4.and the movable contact assembly consisting of the crosshead I5 and the rods I4 and includes the lever 30 and an operating or driving spring 37. The springt? is vreally a double spring as is apparent from the examination of Figure 2 and has opposite pairs of ends, connected to the transverse pin 33-of`lever 3ll` and to a pin 38. The pin 38 is-carried by an insulating guide lever 39 which is connected by means of an insulating link 4B with a lever 4I formed of insulating material. The lever 4I is pivoted as indicated at 42 on the headV 5` ofi the unitary switch and operating mechanism assembly and is provided with a roller 43 at`r its outer. end directly in line with the plungert of the electromagnetic means.

The object of this mechanism is substantially the same as that disclosed in the above noted patent=to Van Ryan et al., Serial No. 2,560,831.

When the plunger 5 moves down upon energization of the electromagnetic motor means. by anfoverload current, it causes the axis of the spring' 31 .to cross the pivot point 3l of the mainlever 30 rand thus moves the main lever down--V wardlywith a very quick motion.y The open position lof -thecircuit'interrupter is shown in Figure l* 5. It is to be noted, however, that the line of'pullv or 4axis of the spring 31 never crosses overfthepivot-point 44 of the guide lever 39 and consequently there is always an upward thrust on the plunger `ii through the medium of the link 4l] and lever 4I'. hereinabove mentioned. Thisup-- wardthrustlis a ybiasing force'which restores the plunger-5 toits initial position shown in Figure 3,y when the circuit is interrupted. As the plunger moves upwardly to the positionyshown' in'iigure 3,. the axis of the spring 31 crosses the pivot point 3 I of the lever 3U and causes the lever toi'riseithereby` closing theswitch.

It is to be noted particularly' that the combined `operating. mechanism and switch assembly can beremoved -as va unit without .disturbing any portionof the electromagnetic motor means or any other portion of. the kbody part I of the circuit interrupter.l If desired ay pin 45,-see Figure 3, may be carried by the upperhead 'I ofthe electromagnetic motor means tand may project into anopening 46 formed inthe heavy Vupper plate 2I. Obviously when the combined operating mechanism and switch assembly are detached from the body portion I of the circuit interrupter, the'entire assembly may be moved downwardly away from the body portion. The pin 45 is rigidly carried bythe head "I of the electromagnetic motor means and freely slides from the aperture' 46.

Itwill be seen that a novel circuit interrupter hasv been provided by this invention which is capable of 'handling a very large overload without damage and which is designed to beused in a high voltage circuit.

It is-.tobe notedfthat the contact rods I4 are located.. outside of the insulating side plates 9 and that the crosshead I5 extends through slots lil-formedinsuch side plates. It has been found that this circuit interrupter can be used in high tension. -lines with a certainty that an arc willl not extend from the contacts to the nearest portion of the metal parts.

It is to be noted further that the relatively wide spacing between the contact mechanism and the metallic portions of the body part of the circuit interrupter is not secured by extending the total length or height of the circuit interrupter. Instead, the switch mechanism is mounted laterally of the body portion of the circuit interrupter and is supported by the relatively heavy insulating side walls which act not only as insulating ballles but also as structural supporting members.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

I claim:

1. A' circuit interrupter comprising a housing having a cover, a main body portion, electromagnetic motor means responsive to overload and constituting a part of the body portion and including a driving member, said body portion being supported from said cover; and an operai-m ing mechanism and switch assembly forming a unitary structure detachably supported from said body portion and said unitary structure being wholly removable as a unit without disassembling said body portion and including a pair of spaced vertical walls of insulating material constituting structural supporting members, operating mechanism supported from said vertical walls and actuated by energy derived from said electromagnetic motor means and delivered through said driving member, and switch means supported from said vertical walls and operated by said operating mechanism, said vertical walls extending laterally outwardly from said body portion and spacing said switch means from said body portion.

2. A circuit interrupter comprising a housing having a cover, a main body portion, electromagnetic motor means responsive to overload and constituting a part of the body portion and including a driving member, said body portion being supported from said cover; and an operating mechanism and switch assembly forming a unitary structure supported from said body portion and including a pair of spaced vertical walls of insulating material constituting structural supporting members, operating mechanism supported by said vertical walls and positioned between said vertical walls and located adjacent one end of said motor means and including insulating lever means projecting laterally outwardly away from said motor means and operated by energy derived from said electromagnetic motor means and delivered through said driving member, and switch means located laterally of said motor means and carried by said vertical walls and operated by said lever means, said operating mechanism and switch assembly being wholly removable as a unit from said body portion without disassembling any part of said body portion.

3. A circuit interruptor comprising a housing having a cover, a main body portion, electromagnetic motor means responsive to overload and constituting a part of the body portion and including a driving member, said body portion being supported from said cover; and an operating mechanism and switch assembly forming a unitary structure supported solely from said body portion and including a pair of spaced vertical walls of insulating material constituting structural supporting members, operating mechanism supported by said vertical walls and positioned between said vertical walls and located adjacent one end of said motor means and including insulating lever means projecting laterally outwardly away from and beyond said motor means and operated by energy derived from said electromagnetic motor means and delivered through said driving member, switch means located laterally of said motor means and carried by said vertical walls, and link means operatively connecting said lever means and said switch means, said operating mechanism and switch assembly being wholly removable as a unit from said body portion without disassembling any part of said body portion.

4. interrupt-er comprising a main body portion, electromagnetic motor means responsive to overload and constituting a part of said body portion and including a driving member; and an operating mechanism and switch assembly forming a unitary structure supported from said body portion and including a pair of spaced vertical Walls of insulating material constituting structural supporting means and insulating barriers, operating mechanism supported between said vertical walls and actuated from said driving member, switch means including stationary contacts located outside of said vertifai Walls and supported by said vertical walls and movable contacts operated from said operating mechanism, said movable contacts including a pair or" rods connected by a crosshead, said rods being located outside oi said vertical walls and said crosshead extending through slots formed in said vertical walls, and an insulating guiding rod arranged to guide said crosshead.

5. A circuit interruptor comprising a main body portion, electromagnetic means responsive to overload and constituting a part of said body portion and including a driving member, a pair of spaced vertical walls of insulating material constituting structural supporting means and insulating barriers, operating mechanism supported between said vertical walls and actuated from said driving member and including a switch operating lever having a pair of rigidly connected arms, switch means suppo 1ted from said vertical walls and including a pair of stationary contacts located outside oi said vertical walls and a pair of movable contacts connected by a crosshead, a single guide rod of insulating material arranged to guide said crosshead, and a pair of links operatively connected to said crosshead and to the arms of said lever, said links being joined by an integrally formed U-shaped member, to thereby prevent rotation of the crosshead about said guide rod.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,624,896 Hill Apr. 30, 1912 2,050,864 Strang Aug. 11, 1936 2,448,695 Van Ryan Sept. '7, 1948 2,449,867 Wallace Sept. 21, 1948 2,521,194 Van Ryan Sept. 5, 1950 2,560,529 Van Ryan et al. July 10, 1951 2,575,738 Wallace et al Nov. 20, 1951 

